Prince George and Princess Charlotte make cheeky appearance at RAF flypast

The royal family were celebrating the centenary of the RAF

It was a momentous occasion to celebrate 100 years of the Royal Air Force, and all eyes were trained to the skies for the spectacular flypast. But Prince George and Princess Charlotte managed to steal some of the limelight as they made an adorable appearance from the window of Buckingham Palace. The royal children had not been confirmed to attend the event, but their surprise outing was no doubt welcomed by fans.

Up to 100 aircraft flew over Buckingham Palace and the display clearly fascinated the youngsters, who looked up at the sky in awe. George, who wore a polo shirt, gave a little wave to the crowds and RAF personnel below while Charlotte, dressed in a blue frock, followed suit and cheekily stuck her tongue out. Their parents Prince William and Kate joined other members of the royal family watching the flypast from the palace balcony.

Kate and Meghan make an elegant appearance at Westminster Abbey:

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Like many youngsters his age, George is mad for helicopters. Kate has previously revealed her son's love for airplanes during an engagement when she chatted to a young boy named Jacob. Jacob's mother recalled: "[Kate] was asking about what Jacob liked and he said he liked aeroplanes and she was asking if he'd seen a Spitfire. We said we liked going to the Science Museum and RAF museum. She was saying how George likes helicopters, she was saying about the top floor of the Science Museum where the helicopters are."

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Charlotte and George watched the flypast from the window

During the family's royal visit to Canada in 2016, George was also invited into the cockpit of a seaplane where he was given the chance – under guidance – to play with some of the controls. Shawn Stewart, the pilot who flew the royals to the base near Victoria International Airport, revealed George's passion for flying.

He said: "After we landed, once the co-pilot got out, George climbed up into the seat and started playing with the controls and pretending he was flying the plane. Kate said: 'Where are you going to fly us? Are you going to fly us to Canada?' And George said: 'No I'm going to fly us to England.' George loved it. He was having fun."

George waved excitedly to the crowds

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The royal family were out on Tuesday to attend a service to celebrate the centenary of the RAF. The Queen, Prince Charles, Camilla, Prince Harry and Meghan joined other royals at Westminster Abbey, before the group headed back to Buckingham Palace for the flypast.

The royal children were looked after by their nanny Maria